516 SCIENTIFIC THOUGHT. 



of vital force. This having been dropped, the question 

 arose for modern biology, What is life ? We thus find 

 thinking biologists of the modern, exact school aiming at 

 a mechanical definition of life. Many answers have been 

 attempted, such as that it is the action of a very com- 

 plex chemical molecule, of dynamical equilibrium, of meta- 

 bolism, of a special form or organisation, &c. Similarly, 

 when the word soul dropped out of psychology in its 

 older metaphysical meaning as a separate being or entity, 

 when it was used to mean only the sum-total of the 

 inner or psychical phenomena, a new problem arose for 

 the psycho-physicist or experimental psychologist. The 

 problem now was to give some definition of the unity 

 and unified totality of all inner or mental phenomena. 

 The older metaphysical psychology, as also for the most 

 part the so-called empirical psychology, answered this 

 question by placing the conception of an independent 

 entity, the soul, person, or self, at the opening of their 

 discussions. Modern exact psychology cannot do this. 

 For it the unity of the inner life and its unified totality 

 has become a problem. This problem Prof. Wundt faces 

 34. fully and fairly. He asks himself the question, Wherein 



The unity of 



conscious- consists the unity of consciousness, wherein the totality 

 of all mental life, individual and collective ? Armed 

 with the methods of exact research, he tries to extract 

 from the whole array of mental phenomena an idea of 

 their essence as distinguished from external or natural 

 phenomena, and of their collective meaning and signif- 

 icance. In so doing he enters the domain of philosophy, 

 and his results belong to the realm of philosophical 

 thought. When dealing with that large section of my 



